<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>高级选择器2</title>
    <style>
        /* :root {
            color: red;
        } */

        /* html {
            color: green;
        } */

        p:not(.p2) {
            color: red;
        }
    </style>
</head>

<body>
    <div>
        <p class="p1">曾经沧海难为水，除却巫山不是云。</p>
        <p class="p2">曾经沧海难为水，除却巫山不是云。</p>
        <p class="p3">曾经沧海难为水，除却巫山不是云。</p>
        <p class="p4">曾经沧海难为水，除却巫山不是云。</p>
    </div>
</body>

</html>